[SOLVED]free space difference

[davidea]

hi guys, i'm an noob it guy, and i have a problema but i can't find the correct word to make a decent search about my problem ..
this night i was halted from an error when creating a new vm,

TASK ERROR: unable to create VM 118 - zfs error: cannot create 'sdd_pool/vm-118-disk-0': out of space

but heyi .. i have a pleanty of disk space, i checkd it before ... (in node- zfs it says 1.16TB and i need only 450gb)


what m'i missing?

i tryed again to create the vm, and when i select the pool where crete the disk, it says 303GB available .... whats wrong??



here the output of zpool

root@dell:~# zpool status sdd_pool -v pool: sdd_pool state: ONLINE status: Some supported and requested features are not enabled on the pool. The pool can still be used, but some features are unavailable. action: Enable all features using 'zpool upgrade'. Once this is done, the pool may no longer be accessible by software that does not support the features. See zpool-features(7) for details. scan: scrub repaired 0B in 00:17:25 with 0 errors on Sun Jan 8 00:41:29 2023 config: NAME STATE READ WRITE CKSUM sdd_pool ONLINE 0 0 0 mirror-0 ONLINE 0 0 0 sdc ONLINE 0 0 0 sdd ONLINE 0 0 0 mirror-1 ONLINE 0 0 0 sde ONLINE 0 0 0 sdf ONLINE 0 0 0 errors: No known data errors root@dell:~#

 

[shanreich]

Can you post the output of

zfs list -o name,used,available,reservation,refreservation

 

[davidea]

root@dell:~# zfs list -o name,used,available,reservation,refreservation NAME USED AVAIL RESERV REFRESERV sdd_pool 1.41T 282G none none sdd_pool/backup 767M 282G none none sdd_pool/subvol-100-disk-0 2.63G 5.37G none none sdd_pool/subvol-204-disk-0 98.1G 282G none none sdd_pool/subvol-205-disk-0 121G 179G none none sdd_pool/subvol-206-disk-0 2.04G 14.0G none none sdd_pool/subvol-207-disk-0 3.69G 6.31G none none sdd_pool/subvol-208-disk-0 5.42G 64.6G none none sdd_pool/vm-101-disk-0 33.0G 310G none 33.0G sdd_pool/vm-102-disk-0 33.0G 295G none 33.0G sdd_pool/vm-103-disk-0 117G 369G none 103G sdd_pool/vm-103-disk-1 3.58M 282G none 3M sdd_pool/vm-103-disk-2 6.09M 282G none 6M sdd_pool/vm-103-state-pre_activation 17.0G 295G none 17.0G sdd_pool/vm-104-disk-0 33.0G 312G none 33.0G sdd_pool/vm-110-disk-0 66.0G 324G none 66.0G sdd_pool/vm-110-disk-1 3M 282G none 3M sdd_pool/vm-110-disk-2 6M 282G none 6M sdd_pool/vm-111-disk-0 3M 282G none 3M sdd_pool/vm-111-disk-1 66.0G 321G none 66.0G sdd_pool/vm-111-disk-2 6M 282G none 6M sdd_pool/vm-113-disk-0 3M 282G none 3M sdd_pool/vm-113-disk-1 103G 345G none 103G sdd_pool/vm-113-disk-2 6M 282G none 6M sdd_pool/vm-114-disk-0 3M 282G none 3M sdd_pool/vm-114-disk-1 103G 366G none 103G sdd_pool/vm-114-disk-2 6M 282G none 6M sdd_pool/vm-115-disk-0 66.0G 307G none 66.0G sdd_pool/vm-116-disk-0 165G 395G none 165G sdd_pool/vm-200-disk-1 66.0G 307G none 66.0G sdd_pool/vm-201-disk-0 20.6G 295G none 20.6G sdd_pool/vm-202-disk-0 17.5G 287G none 17.5G sdd_pool/vm-203-disk-0 82.5G 292G none 82.5G sdd_pool/vm-209-disk-0 6.19G 282G none 6.19G sdd_pool/vm-211-disk-0 210G 435G none 210G root@dell:~#

 

[shanreich]

Looks like there is indeed not enough space, since the CLI tool shows the available space as 282G, which is the proper value.

When creating a disk on the ZFS pool, that amount gets reserved by your disk even if it is not actually used. For instance if you create a disk with a size of 100G but don't store anything on it, then it still reserves that 100G of space - even though it currently uses only very little amount of space.

You can check with the following command:

zfs list -o space

An example output for this command from my test system looks like this:

root@pve:~# zfs list -o space
NAME                               AVAIL   USED  USEDSNAP  USEDDS  USEDREFRESERV  USEDCHILD
zfs_pool/vm-1001-disk-0            2.85T   132G        0B   19.7G           112G         0B

The disk vm-1001-disk-0 shows 132G used, but only a USEDDS of 19.7G. This is because while the disk is actually sized at 132G I am currently only storing 19.7G of data on that disk. The difference can be seen in the column USEDREFRESERV.
This means that while I am currently only using 19.7G of space, ZFS is reserving an additional 112G of space for that disk, since I sized it at 132G.

What you are seeing in the Disks > ZFS view is the amount of space in the USEDDS column, this means that it only shows the space that is currently used, excluding the additional reserved amount. In the disk creation window you can see the amount of space that has not yet been reserved, which is far smaller. This is why even though you are currently only using 743G, you cannot create a disk with 450G - since the remaining space is already reserved by the other disks.

 

[davidea]

thanks for the clear explanation, you pinted me in the right direction!
but maybe in the ZFS panel a new culumn "reserved" and the proper free value will help to clearly see the situation, or change the free culumn to something different

 

[Dunuin]

You pool is also already too full. A ZFS pol shouldn't be filled more than 80% for optimal operation. Fill it more it it gets slower.